Fiber Splicing

Equipment

Splicing Unit

The splicing unit was obtained in December of 2009 from Ron Richards of Michigan State University. Originally it had been used to fuse small round fibers. Some of the equipment has been modified to accommodate the square fibers that will be fused in the unit.

The splicing unit.
The theoretical range of effective melting/splicing

A close-up of the ferrules, collars, and heating lamp of the fiber splicing machine
A side view.

Ferrules

The ferrules are made of quartz, and are V shaped so that they make a hollow square cross-section when mated. This is so the fiber fits between them snugly while it is being fused.

A 2x2 mm square waveguide, 2 ferrules, and heat-shrink used to mount the ferrules and supports to the collars. The black residue on one of the ferrules is RTV and it is used in mounting ferrules to the collars.

Splicing Collars

Prototype collars designed for small round fibers. The top and bottom collars seem to be identical.
The supports and rounded ferrule are mounted.

Top collar, with ferrule and support mounted (machined specifically to mount 2x2mm square fibers).
Bottom collar, with ferrule and support mounted (machined specifically to mount 2x2mm square fibers).

Fibers

Properties of polystyrene

Lamp

The lamp used in the fiber splicing unit is a 25 volt - 250 watt AV/Photo lamp.

Setup

Results

Testing

These are the earliest attempts at splicing 2x2mm square fibers using modified equipment for the splicing unit. Each fiber pictured below had been heated at a different distance from the heat lamp, or for a different length of exposure to the lamp light. As can be seen in the images, there was a gap between the ferrules big enough for cladding or the polystyrene itself to leak through in each attempt. It would seem that the pressure put on the ferrules together, at their ends, is not enough, or the pressure does not translate to the center of the ferrules. Another option was that the ferrules were warping due to the heat from the lamp. Because quartz does not expand/contract much with heat, though, this was considered unlikely.